Income Taxes (Components of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated statements of operations:
Current income taxes	$ 12,528	$ 120,289	$ 188,356
Deferred income taxes (benefits)	56,947	(12,563)	(46,730)
Total income tax expense included in consolidated statements of operations	69,475	107,726	141,626
Stockholders' equity:
Expense (benefit) relating to: Change in net unrealized investment losses	412,117	(240,459)	177,162
Total income tax expense (benefit) included in consolidated financial statements	$ 481,592	$ (132,733)	$ 318,788

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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